Within vacuum process control industries there is a growing demand for smaller, more inexpensive and more reliable valves to isolate certain components in a system and to enable these components to operate under vacuum conditions. There are a number of different types of valves currently known for isolating components in a system. For example, without limitation, rectangular gate valves are the most common in the industry. FIG. 1 illustrates an exemplary rectangular gate valve 100, in accordance with the prior art. A gate 101 of rectangular gate valve 100 moves in a straight line in order to seal rectangular gate valve 100. The movement of gate 101 in the present example is indicated by an arrow 102. Rectangular gate valves typically require an air cylinder to actuate the valve, adding the length of the air cylinder to the overall length of the valve. For example, without limitation, referring to FIG. 1, an air cylinder 103 of gate valve 100 practically doubles the length of rectangular gate valve 100.
Pendulum valves are also currently used in vacuum process control industries. A pendulum valve offers a smaller overall footprint than a rectangular gate valve, making pendulum valves desirable in systems where space is an issue. Rather than sliding in a straight line, the gate of a pendulum valve rotates on a shaft, driven by a set of links that rotate a drive arm and thus the gate of the valve into an opening. The air cylinder required to rotate a pendulum valve can be mounted on the valve body, thus saving space. Pendulum valves currently being used in the vacuum process controls industry typically use a gate that moves parallel to the valve body, and uses a complex series of links and wheels to lock and seal the valve in a closed position. While currently known pendulum valves rotate on shafts to seal the valve closed, there are no wedges or angled surfaces to facilitate the sealing of the valves. Thus, pendulum valves use basically the same mechanism to close and seal the valve as standard rectangular gate valves, for example, without limitation, gate valve 100, shown by way of example in FIG. 9.
In view of the foregoing, there is a need for improved techniques for providing small, reliable and inexpensive valves for use in vacuum pressure systems that uses simple means for creating a vacuum tight seal.
Unless otherwise indicated illustrations in the figures are not necessarily drawn to scale.